Improvement in artificial legs



' Philadelphia, in the county Vtoe-joint.

IUNITED STATES PATENT OEEICEo JESSE BRINGHURST, OF PHILADELPHIA,PENNSYLVANIA.

IMPROVEMENT |N Specification forming part of Letters Patent No. 55,459,dated June l2, 1866; antedated June ARTIFICIAL LEGS.

To all whom it may concern: Y

Be it known that I, JEssE BRINGEUEsT, of of Philadelphia and State ofPennsylvania, have invented a I new and useful Improvement in Artificiall Legs; and I do hereby declare that the following is a full, clear, andexact description of the construction and operation of the same,reference being had to the annexed drawings, making a part of thisspecification, in which- Figure l is a side View. Fig. 2 is a transversesection, Fig. 3 showing bolts, and Fig. 4 showing the ankle-joint. Fig.5 represents the My present invention has for its object the productionot' an artificial leg constructed on such principles that it will givemore strength and durability to the limb, and also ease and comfort tothe wearer. The improvements consist in a more perfect construction ofthe ankle, knee, and toe joints. Y

To enable others skilled in the art to makel and use my invention, Iwill proceed to describe its construction and operation.

In said drawings, A represents a wooden limb (it may, however, be metal)ofthe proper form, being flexible at the joints B B B.

My first and greatfobject is to construct in such a manner as to securea long and solid bearing for the steel or metallic bolts in wood. I thenconstruct the bolts C of the proper length and diameter to suit thejoints B B', I carefully turned, the smallest diameter being' at the endof the bolt, upon which a screwthread is cut to fit one ofthe sidestraps upon the leg. A greater diameter is then allowed for the bearingin wood, and then the greatest diameter nearest the head of the bolt forthe second screw-thread, which is to it the re- *naining side stra Thebolt is also drilled anltapped at the small end with an opposite C.Between thread to that on the outside, and a small screw, D, placedtherein. It will be readily be seen that the side straps will besecurely held at a positive distance from each other, and therebyprevent the friction occasioned by shrinkage and warping ofthe wood. ThesmallscrewD will prevent the bolts from working out while in use. At theankle-joint B', I place a metallic swivel-box, E, securely held to thefoot by two metallic bearin gs, F, hushed with wood. The metallic box Eis bored, hushed with wood, and rebored to tit the bolt the box justdescribed and the foot I place a piece ot' india-rubber, H, or itsequivalent, and by so doing give the foot a y flexibility so necessarywhile walking over uneven surfaces.

At the toe-join t, marked B, I make a rulejoint tapering toward Atheoutside of the foot. On both sides of the toe-piece I firmly fasten twometallic plates, G, by means of the wires I, passing through thetoe-piece and riveted thereto. I likewise put an additional wire throughthe joint and rivet it firmly, making a durable joint the whole width ofthe foot.

The leg may be finished by any of the many appliances adapted torepresent the natural cords or tendons.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. TheV bolt C, as described, and for the purpose set forth.

2. The swivel-box E, in combination with the bolt C and rubber packingH, as specified, and for the purpose set forth.

JESSE BRINGHUBST.

therebyv

